An MRI scanning procedure requires a coordinated effort among many pieces of hardware and software. Collection of scan data and production of images from the scan data must be carried out with precision if the resulting images are to have diagnostic value. Glitches in the procedure, due to hardware fatigue, software malfunction, electrical noise, temperature effects, or any other deviation by any operational parameter outside of an acceptable tolerance can have a negative effect on the results.
For example, timing problems in pulse sequence hardware and firmware can cause image artifacts due to shifting of pulse sequence waveforms. In a typical MRI scanner a pulse sequence system governs the timing and control of scanning devices. A stream of control data, typically generated by software on a PC, is transferred to a controller that times the provision of data to the various devices. Often, an intermediate processor receives the control data in a stream, buffers the control data, and provides blocks of the control data to the controller, which typically is hardware that resides on a circuit board.
The timing of the data transfer to the controller is determined by interrupts generated by the controller and provided to the intermediate processor. Occasionally, timing aberrations in the interrupt sequence result in device miscues, which in turn result in artifacts in the resulting image. If the timing errors are not detected, or if they are only reported at the end of a scan procedure, the artifacts will be present in the images, and the scan procedure might have to be repeated.
It would be advantageous to detect operational parameter deviations and other errors during the course of the scan procedure. It would also be advantageous to provide a report of these errors, and to act on the report during the scan procedure to correct portions of the scan procedure sequence while the procedure is taking place, so that the resulting image will be sufficient for diagnostic use.